Change speed gearing



Sept. 3, 1935. c. R. H. BONN 1 CHANGE SPEED GEARING Filed Jan. 26, 19545 Sheets-Sheet l Sept. 3, 1935. c. H. BONN 2,013,125

CHANGE SPEED GEARING Filed Jan. 26, 1954 s Sheets-Sheet 2 P 3, I c. R.H. BONN Q 2,013,126 7 I CHANG-E SPEEDQGIEARING Filed Jan. 26, 1954 v sSheets-Sheet 3 FIG- l'z nzwf I Patented Sept. 3, 1935 PATENT OFFICECHANGE SPEED GEARING Carl Robert Hugo Bonn, Glasgow, ScotlandApplication January 26, 1934, Serial No. 708,374

' In Great Britain January 26, 1933 12 Claims.

Thisinventlon relates to variable speed gearing of the epicyclic geartype and includes an epicyclic variable speedgear in which the speed ofthe driven shaft is varied relatively to the speed of the driving shaftby an axially movable planet carrier operable in a pressure fluidcircuit.

Desirably the planet carrier of each geartrain presents the annulus ofan adjacent gear train and is constituted by a disc which presents abrake surface adapted to engage a corresponding brake surface presentedby an enclosing box or casing by being moved axially by pressure fluid.The planet carriers, operable in the pressure fluid circuit, may bemoved axially upon actuation of inlet and exhaust valves adapted tocontrol the fluid pressure applied to said carriers and which may beoperatively connected together.

The pressure fluid circuit includes the inlet and exhaust valves, apump, passage connections between said pump and valves, the epicyclicgear trains, the casing enclosing said trains, and a conduit connectingthe one end of said casing to the suction side of said. pump.

In the accompanying drawings Fig. 1 is a sec tional view of anembodiment of epicyclic variable speed gearing according to theinvention, the portion at the left hand side, which includes the pumpandpump casing, being a section on a vertical plane and the remainder ofthe view, which ineludes the gear box, being a section on a horizontalplane.

Fig. 2 is a fragmentary sectional elevation,

Fig. 3 is a diagrammatic plan and'Fig. i is a die grammatic end viewillustrating the gearing for obtaining a reverse drive to the drivenshaft.

Fig. 5 is a fragmentary sectional elevation of the inlet and exhaustvalves.

Fig. 6 is a diagram to illustrate the operation of the apparatus, and

Fig. 7 is a fragmentary sectional elevation of a modification forobtaining a fifth or extra speed and Fig. 8 is an elevation of the gearcasing at right angles to Fig. l. According to the embodiment of theinvention illustrated. by Fig. l epicyclic change speed gearing includesacasing l th inner surface of the annular wall of which is of truncatedconical formation; The driving shaft 2 passes axially into the casing ifrom the end of smaller diameter and extends to near the end of largerdiameter. The driven shaft 3 passes axially into the casing i from theend of larger diameter. Conveniently the end 2, of the driving shaft 2is mounted in a socket 3 provided in the adjacent end of the drivenshaft 3. Roller bearings land an end-= thrust ball bearing 4' may beinterposed between the ends 2, t of the shafts 2 and 3 and said shaftsmay be supported by ball or like bearings 5 carried by the end walls ofthe casing l.

A plurality of sun pinions 6, t, t are secured 5 on the driving shaft 2and gear with corresponding planet pinions l, l, i of which the planetpinions 'l' and l are mounted for rotation on studs't', 8 carried,respectively, by disc members 9' and 9 mounted for rotation and foraxial no movement on sleeves it and Hi secured on the driving shaft 2.The discs 9' and t each carrya toothed annulus M and H with which,respectively, the planet pinions land l engage. The pinion l engageswith a toothed annulus H presented by a disc 9 mounted for rotation andaxially slidable on a sleeve m mounted on the boss of a disc 9 securedon the shaft 2. The disc 9 also presents a toothed annulus M the teethof which mesh with a toothed wheel pre- 2 sented by a disc member ifmounted for rotation and axially slidabl'e on a stationary boss whichmay be presented by the end wall of the casing i A cage, presented byrings til, Figs. 1, 2, 3 and t is carried by the end i of the drivenshaft as t by means of plate members B ithe rings it! and the plates itbeing secured together by bolts l5; Pairs of axle pins 8 and it extendbetween the rings it. The planet pinions l are mounted on the axle pinst and secured to each pinion i is to a pinion ii. On each axle pin itintegral pinions it and it are mounted. The pinions Ill engage with thepinions it. The pinions it gear with a toothed annulus it presented by adisc 9 mounted for rotation and axially slidable on the it driven shaft3. The peripheral surfaces of the discs t, t, t and W are of truncatedconical formation to correspond to the formation of the inner surface ofthe annular wall .of the casing I and the peripheral surface of the disct presents 410 a truncated conical surface to correspond with a similarsurface presented by the disc it; Desirably, the discs t, t, t t t andit are of dished formation.

The annular wall of the casing l is provided it with a plurality ofports it, til, M and 2m through which pressure fluid, such as oil underpressure, is admitted to and exhausted from the casing i on one side orother of the discs 9, 9', a or W.

The ports it to 26 are open to compartments 2i presented by spaced walls22 integral with the casing 9.

A valve box 23, Figs. 1 and 5, fitted against the compartments M isprovided with an' inlet valve 24 and an outlet or exhaust valve 25. Thevalves 24 and 25 are each constituted by a close-ended tube providedwith spaced valve ports 26 and 26', there being an inlet valve port 26and an exhaust valve port 26 for each compartment 2|. The setting orarrangement of the ports is such that when one compartment is open topressure fluid the adjacent compartment or compartments on the sidetowards the smaller end of the casing I is open to exhaust. The valves24 and 25 are geared together by gear wheels 21. One valve, desirablythe inlet valve 24, may be provided with a handle 28 secured on thevalve spindle 29 and cooperative with a disc 30 whereby the position ofthe valve ports may be indicated. Angular movement of the valves 24 and25, by means of the handle 29 admits or exhausts pressure fluid to oneor other of the compartments 2|.

The pressure fluid which actuates the discs presenting the clutches iscirculated in a pressure fluid circuit indicated diagrammatically byFig. 6 which includes a tank 3I desirably carried by the casing I, Figs.6 and 8, a pump 32, Figs. 2 and 6, desirably carried by a casing 32secured. to the end wall I of the casing I, a pressure relief valve 33,Figs. 6 and 8, incorporated in a conduit 34 connecting the dischargeside of the pump 32 and the tank 3|, the inlet and exhaust valves 24 and25 Figs. 1 and 8, a conduit 34' between the pump and inlet valve 24, anoverflow conduit 35 connecting the larger end of the casing I with thetank 3 I, a constricted throat 36 presenting a nozzle to restrict theflow of pressure fluid through said overflow conduit 35, a chamberpresenting a conduit 31 connecting the inlet valve 24 and the smallerend of the casing I, a constricted throat 38 presenting a nozzle torestrict the flow of pressure fluid through said conduit 31, a chamberpresenting a conduit 31' connecting the smaller end of the casing I andthe exhaust valve 25, the ports 20 to 20, the compartments 2| and theinterior of the casing I.

Desirably the pump 32 is driven from the shaft 2 by means of a train ofgear wheels 39.

If desired and as shown, the disc I2 may present a toothed wheel 40adapted to mesh with a toothed wheel 4I presented by a sleeve 42 looselymounted on the shaft 2 and provided with a toothed wheel 43. A train ofgear wheels 44 may be provided between the wheel 43 and the pump shaft32 is associated with a free-wheel pawl and ratchet device 39' and 44'.Conveniently the free-wheel devices 39' and 44' are fitted to the lastwheel of their respective trains and the wheels constituting the trainsare selected so that the last wheel of the train 39 rotates at a fasterspeed than the last wheel of the train 44.

Normally the pump shaft 32 is driven from the main shaft 2 by means ofthe gean train 39 and as the last wheel of said gear train rotatesfaster than the last wheel of the gear train 44 the said gear train 44runs idle, the pump shaft 32 overrunning the last wheel of the geartrain 44.

In the event of the power driving the shaft 2 failing or being cut-offand the driven shaft 3 continuing to rotate the pump shaft 32 will'bedriven through the epicyclic gears in the casing the last wheel of thegear train 44 taking up the drive to the pump shaft.

If desired the toothed wheel 40 presented by the disc I2, the toothedwheel H and the sleeve 42 may be dispensed with whereby the pump shaftEach gear train 39 and 44 32 may be driven only from the shaft 2 and inorder that the direction of rotation of the shaft 2 may be reversedwithout reversing the direction of rotation of the pump shaft 32 thetoothed wheel 43 may be secured on the shaft 2, the pawl and ratchetfree wheel devices being reversed, or the gear train 44 may include agear wheel more than the gear train 39, whereby one gear train runs idlewhile the other is driving the pump shaft.

The flow of pressure fluid from the inlet valve 24 through the conduit31 is controlled by a ring of ports 26 Fig. 6, in said inlet valve, aport 26 being provided to correspond to all positions of the inlet valveexcept the position presenting a solid drive wherein the pressure fluidis admitted to the casing I through the port 20 In operation the pump 32circulates pressure fluid through the circuit, the relief valve 33preventing excessive pressure.

In the free or neutral position of the epicyclic speed gearing pressurefluid circulated by the pump 32 passes through the conduit 34' to theinlet valve 24 and through the ports 26 conduit 31 and nozzle 38 to thesmaller end of the casing I whereby all the discs 9 to 9 are moved tothe disengaged or free position. The inlet and exhaust ports are allclosed and the pressure fluid at the larger end of the casing I leaksback to the tank 3I through the conduit 35 and nozzle 36.

When the variable speed gearing is in top speed, presenting a soliddrive between the driving and driven shafts the flow of pressure fluidfrom the inlet valve 24 through the conduit 31 and nozzle 38 is cut offby closure of the ports 26 and pressure fluid passesfrom said inletvalve 24 as indicated in Fig. 8 by the line 45 through the port 20 andis discharged to the exhaust valve 25 through the conduit indicated bythe line 45 and 46' Fig. 6.

In other variable speed gear positions the conduit 31 includingthenozzle 38 and the smaller end of the casing I are open to pressurefluid, one or other of the inlet ports 20 to 20 and a correspondingexhaust port are open and the other inlet and exhaust ports are closed.In all cases the conduit 35, including the nozzle 36, from the largerend of the casing I to the tank 3I or pump suction is open.

When a disc is held by contact with the casing I the pressure fluidadmitted through the nozzle 36 presses on any disc which may be in" onthe non-pressure side of the held disc and moves it to the freeposition, the fluid thus admitted ultimately escaping back to the pumpsuction by the open exhaust port. Similarly the pressure fluid admittedby the open pressure port presses on any disc which may be in on thepressure side of the held disc and moves it to the free position,pressure fluid passing these discs escaping back to the pump suctionthrough the nozzle 36.

To obtain a reverse drive to the shaft 3 pressure fluid is admittedthrough the port 20 behind the disc 9 which is moved axially until itsperipheral surface contacts with the inner surface of the annular wallof the casing I. The disc 9 is thereby locked or clutched againstrotation. Pressure fluid is exhausted through the port 29' and throughthe exhaust valve from the other side of the disc 9, On rotation of thedriving shaft 2 the sun pinion 8 rotates the planet pinions 1 andtherefore the pinions I1 on the axle pins 9. The pinions I1 rotate thepinions I9 and is on the axle pins l6 and as the annulus ii is heldagainst rotation the pinions on the axle pins perform an orbitalmovement round the shaft 2 thereby driving the cage which by means ofthe plates l4, drives the shaft 3 in the reverse direction to the shaft2.

During the reverse drive when the disc 9 is held against rotation theother discs are free and idle.

To obtain a forward first speed drive the inlet and exhaust valves 24and 25 are actuated whereby pressure fluid is admitted through the portill, the port 20 being open to exhaust, so that the disc is movedaxially until its peripheral surface contacts with the casing 11. Thedisc ii is thereby clutched against rotation and the other discs arefree. The sun pinion 6 drives the planet pinion i and as the annulus iiis stationary the pinion i performs an orbital movement whereby thecage, by means of the plates id, drives the shaft 3 in. the samedirection as the shaft 2, the pinions ii, id, and iii being free andidle.

To obtain a forward second speed drive pressure fluid is admittedthrough the port W and the port 20 is open to exhaust whereby the disc 9is moved axially until its peripheral surface contacts with the casingi. The disc is thereby held against rotation and the other discs arefree. The sun pinion 6' drives the planet pinion 'i' which, as theannulus it is stationary performs an orbital movement and rotates thedisc 9 which, by means of the annulus ii, imparts an orbital movement tothe pinion i whereby, as the annulus Ii is .free, the cage and thereforethe driven. shaft'3 are rotated.

To obtain a forward third speed drive pressure fluid is admitted throughthe port re and the port 26 is open to exhaust, whereby the disc 9 ismoved axially until its peripheral surface contacts with the casing i.The disc 9 is thereby held against rotation and the other discs arefree. The sun pinion 6 drives the planetpinion I which, as the annulus ii is stationary, performs an orbital movement and rotates the. disc '9which by means of the annulus ii, imparts an orbital movement to theplanet pinion 'i and rotates the disc 9' which by means of the annulus iI imparts an orbital movement to the pinion I whereby, as the annulus IIis free, the cage and the driven shaft 3 are rotated.

To obtain a forward fourth speed or solid drive, pressure fluidis'admitted throughthe port 20 and moves the disc l2 axially whereby theclutch surface of said disc clutches with the corresponding surface ofthe disc 9 which is secured to the shaft 2. The disc I2 is in gear withthe annulus i Ii of the disc 9 and since all the discs 9 to 9 are out ofcontact with the casing i and all the sun pinions are secured on theshaft 2 and in gear with the planet pinions the whole gear rotates as aunit or solid drive.

If desired the modification illustrated by Fig. 9 may be provided forobtaining a forward fifth speed drive.

As shown by Fig. 7 an additional port it is provided at the larger endof the casing i behind an additional disc t carried by a sleeve itloosely mounted for axial movement on the end 3' of the driven shaft 3.

When pressure fluid is admitted through the port 20" the disc is movedaxially until it is clutched by the casing i. tn the sleeve in isthereby held stationary and imparts to the planet pinions engagingtherewith an orbital movement resulting in the rotation of A pinion iisecured,

the cage and'driven shaft 3, the cage being rotated through the sun andplanet pinions 6 and i.

I claim:-

l. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, an axially movableplanet carrier incorporated in said assembly, a

presented by the disc member, means for supplying pressure fluid to saidcasing and means for controlling the supply of pressure fluid to saidcasing whereby said disc is moved axially.

3. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, axially movable discmembers constituting planet carriers incorporated in said assembly, abrake surface presented I by the periphery of each disc member, a casingenclosing said assembly, a brake surface presented by said casing andadapted to cooperate with the brake surfaces presented by the discmembers, means for supplying pressure fluid to said casing and means forcontrolling the supply of pressure fluid to said casing whereby one ofsaid discs is moved axially. A

4. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, axially movableplanet carriers incorporated in said assembly and adapted to be heldagainst rotationor left free to retateig'a casing enclosing saidassembly, a pump for supplying pressure fluid to said casing and rhea sfor controlling the supply of pressure fluid to sa d casing whereby saidplanet carriers may be maintained in the free position by pressure fluidadmitted to one end of said casing, the other end of which is open tothe pump suction.

5. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a' driven shaft, an axially movableplanet carrier incorporated in said assembly, a casing enclosing saidassembly, means for supplying pressure fluid to said casing, and meansfor controlling the supply of pressure fluid to said casing whereby saidplanet carrier is moved axially to divide said easing into compartmentswhereby one of which may be open to pressure fluid and another of whichmay be open to exhaust.

6. Variable speed gearing interconnecting a driving shaft and a drivenshaft and comprising an assembly of epicyelic gear trains each of whichincorporates an axially movable planet carrier and an annulus, theplanet carrier of one train presenting the annulus of an adjacent geartrain, a brake surfacepresented by the periphery of each planet carrier,a casing enclosing said assembly, a brake surface presented by saidcasing and adapted to co-operate with the brake surfaces presented bythe planet carriers, means for supplying pressure fluid to said casingwhereby said planet carrier is moved axially for co-op eration of thebrake surfaces, and means for controlling the supply of pressure fluidto said casing.

7. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, an axially movabledisc member constituting a planet carrier incorporated in said assembly,a brake surface presented by said disc member, an annular wall and endwalls which constitute a casing enclosing said assembly, a brake surfacepresented by said annular wall and adapted to co-operate with the brakesurface presented by the disc member, ports formed in said annular wall,means for supplying pressure fluid through said ports to said casing andvalves adapted to control the flow of pressure fluid through said ports.whereby said disc is moved axially for co-operation of the brakesurfaces.

8. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, an axially movabledisc member constituting a planet carrier incorporated in said assembly,a brake surface presented by said disc member, an annular wall and endWalls which constitute a casing enclosing said assembly, a brake surfacepresented by said annular wall and adapted to co-operate with the brakesurface presented by the disc member, ports formed in said annular wall,means for supplying pressure fluid through said ports to said casing,inlet and exhaust valves adapted to control the flowof pressure fluidthrough said ports, whereby said disc member is moved axially forco-operation of the brake surfaces and means for operativelyinterconnecting said valves.

9. Variablespeed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, an axially movableplanet carrier incorporated in said assembly, a brake surface presentedby said planet carrier, a casing enclosing said assembly, a brakesurface presented by said casing and adapted to co-operate with thebrake surfaces presented by the planet carrier, a pump for supplyingpressure fluid to said casing, operatively connected inlet and exhaustvalves for controlling the pressure fluid supply to and exhaust fromsaid casing, whereby said planet car-- rier is moved axially forco-operation of the brake surfaces, and a conduit connecting the one endof said casing and the suction side of said pump.

10. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, an axially movableplanet carrier incorporated in said assembly, a brake surface presentedby said planet carrier, a casing enclosing said assembly, a brakesurface presented by said casing and adapted to co-operate" with thebrake surfaces presented by the planet carrier, a pump for supplyingpressure fluid to said casing, operatively connected inlet and exhaustvalves for controlling the pressure fluid supply to and exhaust fromsaid casing, wherebysaid planet carrier is moved axially forco-operation of the brake surfaces, a conduit connecting the one end ofsaid casing and the suction side of said pump and a constricted nozzleincorporated in said conduit.

11. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, an axially movableplanet carrier incorporated in said assembly, a brake surface presentedby said planet carrier, a casing enclosing said assembly, a brakesurface presented by said casing and adapted to co-opcrate with thebrake surfaces presented by the planet carrier, a pump for supplyingpressure fluid to said casing, operatively connected inlet and exhaustvalves for controlling the pressure fluid supply to and exhaust fromsaid casing, whereby said planet carrier is moved axially forco-operation of the brake surfaces, a passage connecting said inletvalve and an end of the casing and a constricted nozzle incorporated insaid passage.

12. Variable speed gearing including an epicyclic gearing assemblyinterconnecting a driving shaft and a driven shaft, a casing enclosingsaid assembly, a pump for supplying pressure fluid to said casing, agear train interconnecting the driving shaft of the gearing assembly andthe pump shaft, a sleeve loosely mounted on the driving shaft of thegearing assembly and adapted to be driven through gears from the drivenshaft of said assembly, a second gear train interconnecting said sleeveand the pump shaft, and a pawl and ratchet free-wheel deviceincorporated in each of said gear trains whereby when one of said trainsdrives the pump shaft the other gear train runs idle.

CARL ROBERT HUGO BONN.

